1. Field of the Invention
This invention relates to a filter structure in connection with a surface cleaning apparatus.
2. Description of the Prior Art
There are known to be in the prior art cleaning machines which recycle the cleaning fluid used, the machines having filters embodied therein for the recovery of cleaning fluid and its continued use.
An example of the prior art in U.S. Pat. No. 2,223,963 to Nadig in which a rotary head distributes cleaning fluid and a suction line is provided to recover the cleaning fluid to recycle the same for further use but there in no provision for the removal of contaminants from the fluid.
In. U.S. Pat. No. 1,670,934 to Keefer, there is disclosed a scrubbing machine in which a brush is mounted upon a horizontal axis and a fan is used to create suction in the scrubbing chamber. Resulting from the cleaning effort, a mixture of air, dirt, and cleaning fluid is removed by suction into a chamber wherein the dirt settles and a pump attempts to recover the fluid for re-use.
In U.S. Pat. No. 4,466,155 to the applicant there is disclosed a tank which received cleaning fluid recovered from a cleaning application and embodied within the tank is a filter in connection with the outlet line for the re-use of the cleaning fluid, the filter having the tendency to having its outer surface become clogged with the contaminants removed from the recycled cleaning fluid.